The present invention relates generally to a system and method of detecting the presence of a person (or other living being such as a dog or cat or any other pet or animal) in a vehicle compartment such as a trunk or interior cabin compartment, and, more particularly, to an improved system and method for detecting the presence of a person in a vehicle trunk or passenger compartment. Specifically, the present invention comprises a vehicle compartment occupancy detection system that uses electric field sensing to detect the presence of a person in a vehicle compartment. Preferably, the present invention comprises a respiration detection system that includes a respiration transducer that uses electric field sensing to detect the presence of a person in a vehicle compartment.
Entrapment of persons, particularly children, in vehicle compartments, such as interior cabins and trunks, is a known danger. A variety of solutions have been proposed such as those based on radar, ultrasonic, active and passive infrared, thermopiles, image sensors, carbon dioxide sensors, bolometers, and thermal imaging camera technologies. In addition, these sensors can be combined with other systems, such as pressure sensitive mats placed in the vehicle compartments and/or shock sensors, level sensors, and microphones. Many such prior occupant detection systems detect a movement, however, and such systems may fail to detect the presence of, for instance, a sleeping or moribund child. In the case of car-jacking victims or the like who are placed in the trunk of a vehicle while unconscious, the unconscious victim will be unable to activate a manual release handle and/or move so as to trigger a motion detector.
In addition, the interior compartment of a vehicle represents a danger to both humans and pets, particularly during hot weather. In the summer months, the interior temperature of a car can exceed 150 degrees Fahrenheit due to the greenhouse effect from the glass windows. Children, in particular, can suffer life-threatening illnesses, most notably heat stroke, when exposed to temperatures of this level. In some cases, parents will leave a sleeping child in a car for some period of time, rather than waking the child. Thus, there is a need for a system that can detect a sleeping or unconscious child to prevent tragedies at high temperatures.
The present invention is intended to provide a compartment occupancy detection system which is operable to detect the presence of a person or animal within a compartment, such as a trunk or cabin of a vehicle. The present invention is preferably operable to generate an electric field in a portion of a vehicle compartment and detect respiration or movement of a person or animal within the compartment by detecting a change in an electric field established within the compartment being monitored. The present invention may be further operable to actuate an accessory of the vehicle and/or to communicate an alert to a person remote from the vehicle in response to a detection of a person within the vehicle compartment and a detection of a hazardous condition within the vehicle compartment.
According to an aspect of the present invention, a vehicle compartment occupancy detection system for detecting the presence of a person in a vehicle compartment includes at least one electric field sensor which is operable to detect occupancy in the vehicle compartment by detecting a change in an electric field within the compartment; the change in the electric field being indicative of a presence of a person within the compartment. Preferably, the change in the electric field is indicative of a biometric characteristic of a person, and, more preferably, the change in the electric field is indicative of respiration of a person or animal within the vehicle compartment. The sensing system may be positioned within a cabin or trunk compartment of the vehicle.
In one form, the vehicle compartment sensing system includes at least one electric field generator which is operable to generate the electric field within the vehicle compartment. The electric field generator may include at least one transmitting electrode, while the electric field sensor may include at least one receiving electrode. In another form, the electric field sensor may be further operable to generate the electric field within the vehicle compartment.
In one form, the vehicle compartment sensing system further includes a microprocessor which is operable to receive a signal from the electric field sensor and to receive at least one input and/or to output at least one output. The output may be in response to the input being indicative of a hazardous condition within the vehicle compartment and of a person being detected within the vehicle compartment. The output may be a corrective action to at least partially alleviate the hazardous condition and/or a communication to communicate to a person exteriorly of the vehicle that the hazardous condition exists. The output may include a communication with a remote receiver, activation of a ventilation system of the vehicle, actuation of at least one of a horn or a light of the vehicle, activation of a security system, unlocking of the doors of the vehicle, opening of at least one window of the vehicle, and activation of a remote transducer. The input may include a temperature input indicative of a temperature within the vehicle compartment, a door lock status, a door position, a window position, a vehicle motion status, an ignition position, a signal from a radar detector within the vehicle compartment, a signal from an ultrasound detector within the vehicle compartment, a signal from an imaging detector within the vehicle compartment, a signal from a carbon dioxide detector within the vehicle compartment and/or a signal from a carbon monoxide detector within the vehicle compartment.
Optionally, the vehicle compartment sensing system may include a timer. The sensing system may be operable to monitor the electric field sensor for a period of time following an activating event, such as receiving a signal which is indicative of a person exiting the vehicle, and then to deactivate at the end of the period of time.
According to another aspect of the present invention, a vehicle compartment sensing system for detecting the presence of a person in a vehicle compartment includes at least one electric field generator which is operable to generate a electric field within the compartment, at least one electric field sensor which is operable to detect the electric field within the vehicle compartment, and a control which is operable to determine occupancy of the vehicle compartment in response to a change in the electric field being detected by the electric field sensor. The change in the electric field being indicative of respiration of a person within the vehicle compartment.
Preferably, the control is operable to actuate at least one accessory in response to the detected change in the electric field. The control may further be operable in response to at least one input, whereby the control is operable to actuate at least one accessory in response to the change in the electric field and the input. The accessory may include at least one of a communication system, a security system, a door lock system of the vehicle, a window of the vehicle, a ventilation system of the vehicle, an air conditioning system of the vehicle, a heater of the vehicle, a light of the vehicle and a horn of the vehicle.
According to another aspect of the present invention, a method for sensing the presence of a person in a vehicle compartment includes providing at least one electric field sensor at the vehicle compartment, and sensing a change in an electric field within the vehicle compartment which is indicative of a presence of a person within the vehicle compartment.
Preferably, the method includes sensing at least one vehicle characteristic and actuating at least one accessory in response to the vehicle characteristic and the electric field sensor. The vehicle characteristic may be one or more of a temperature within the vehicle compartment, a door lock status, a door position, a window position, a vehicle motion status, an ignition position, a signal from a radar detector within the vehicle compartment, a signal from an ultrasound detector within the vehicle compartment, a signal from an imaging detector within the vehicle compartment, a signal from a carbon dioxide detector within the vehicle compartment and a signal from a carbon monoxide detector within the vehicle compartment.